LIGHT UNFLAVORED MESONS
($\boldsymbol S$ = $\boldsymbol C$ = $\boldsymbol B$ = 0)
For $\mathit I = 1$ (${{\mathit \pi}}$, ${{\mathit b}}$, ${{\mathit \rho}}$, ${{\mathit a}}$): ${\mathit {\mathit u}}$ ${\mathit {\overline{\mathit d}}}$, ( ${\mathit {\mathit u}}$ ${\mathit {\overline{\mathit u}}}−$ ${\mathit {\mathit d}}$ ${\mathit {\overline{\mathit d}}})/\sqrt {2 }$, ${\mathit {\mathit d}}$ ${\mathit {\overline{\mathit u}}}$;
for $\mathit I = 0$ (${{\mathit \eta}}$, ${{\mathit \eta}^{\,'}}$, ${{\mathit h}}$, ${{\mathit h}^{\,'}}$, ${{\mathit \omega}}$, ${{\mathit \phi}}$, ${{\mathit f}}$, ${{\mathit f}^{\,'}}$): ${\mathit {\mathit c}}_{{\mathrm {1}}}$( ${{\mathit u}}{{\overline{\mathit u}}}$ $+$ ${{\mathit d}}{{\overline{\mathit d}}}$ ) $+$ ${\mathit {\mathit c}}_{{\mathrm {2}}}$( ${{\mathit s}}{{\overline{\mathit s}}}$ )
INSPIRE search

${{\boldsymbol \eta}{(1760)}}$ $I^G(J^{PC})$ = $0^+(0^{- +})$ 

Seen by DM2 in the ${{\mathit \rho}}{{\mathit \rho}}$ system (BISELLO 1989B). Structure in this region has been reported before in the same system (BALTRUSAITIS 1986B) and in the ${{\mathit \omega}}{{\mathit \omega}}$ system (BALTRUSAITIS 1985C, BISELLO 1987 ).
${{\mathit \eta}{(1760)}}$ MASS   $1751 \pm15$ MeV 
${{\mathit \eta}{(1760)}}$ WIDTH   $240 \pm30$ MeV 
$\Gamma_{1}$ 4 ${{\mathit \pi}}$  823
$\Gamma_{2}$ 2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}$  seen 819
$\Gamma_{3}$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$2 ${{\mathit \pi}^{0}}$  seen 822
$\Gamma_{4}$ ${{\mathit \rho}^{0}}{{\mathit \rho}^{0}}$  seen 407
$\Gamma_{5}$ ${{\mathit \rho}^{+}}{{\mathit \rho}^{-}}$  seen 407
$\Gamma_{6}$ ${{\mathit \omega}}{{\mathit \omega}}$  seen 393
$\Gamma_{7}$ ${{\mathit \eta}^{\,'}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$  seen 572
$\Gamma_{8}$ ${{\mathit \gamma}}{{\mathit \gamma}}$  seen 876